Mini-excavators are generally understood to be micro-excavators which travel on rubber crawler tracks. These machines can drive through door openings of a carcass and are used as so-called construction robots with hydraulic hammers instead of excavator shovels also when renovating buildings.
With such mini-excavators, the aim is undertaken to carry the greatest possible fuel supply despite the very small dimensions. Thanks to this measure, the required refuelling intervals can be kept large. In a similar way, a large supply of hydraulic oil leads to an extension of the oil-change intervals. Furthermore, a large available oil supply improves the oil cooling of the excavator hydraulics.
At the same time, however, an operator's cabin should be made as comfortable as possible for the operator. For example, a driver's seat should be designed with sufficient suspension, which, however, requires a lot of room in the operator's cabin. In the operator's cabin, room is additionally required for a battery, a cabin heater and, for example, for an instrument panel. As the devices named can, in total, often only be fitted with difficulty in an operator's cabin, occasionally open operator's platforms are used, for example with a roll-over bar. To provide an appropriate size to the operator's cabin, the two fluid tanks named above are normally fitted below the driver's seat or in the engine compartment. However, this has the consequence that, for example, when the fuel tank is disposed below the driver's seat, there is no room left for a cabin heater. The disposition of the hydraulic oil tank in the engine compartment, on the other hand, leads to a warming of the oil due to the engine heat so that larger oil coolers are required which, in turn, leads to increased room requirements and/or lowers the engine accessibility.
Another problem which occurs, in particular with mini-excavators, is that due to the strict dimension specifications, the insulation of the engine compartment or of the valve box of the excavator is only possible in an insufficient manner. For the reasons given above, sound-proofing layers of thick construction such as are usual with larger machines cannot be used with mini-excavators.